Am I wrong for being upset with my family about this?

So for context, my parents and I are pretty much no contact/estranged from my older sister. I have her blocked on my phone and social media and have not spoken to her in several years. She pretty much only goes around my grandparents and stays at their house 50% of the time. When we are visiting my grandparents, my sister stays upstairs in her room.

She got a dog at the shelter about 7 months ago- it’s a large bull mastiff that is also at their house when she is there. The dog seems timid as if he may have been abused by past owners.

My mom and dad were at my grandparents house watching the Super Bowl. My sister was upstairs and the dog was downstairs where everyone else was watching TV. My mom’s glasses accidentally fell off the top of her head and landed on the carpet. As my mom bent down to pick her glasses up, the dog lunged at my mom’s face and bit it her face out of nowhere. My mom truly thought her face was ripped off- blood was everywhere. It was only millimeters away from getting her eye. She now has a black eye and huge bruise on her cheek, possible cheekbone fracture, her face is extremely swollen to the point her eye won’t close all the way causing vision problems, and extreme pain. She also has some nerve damage that prevents one side of her face from moving- when she smiles only half of her mouth moves.

The dog made a vicious sound when it attacked and my sister heard it and yelled angrily downstairs, “who is messing with my dog?” My mom was still bleeding profusely and my mom was saying that until now she didn’t realize why some people were scared of dogs but now she gets it because she is afraid now. My grandma’s response was to say “well maybe that’s why this happened, so you could have empathy for people.” At this point my mom went home.

Flash forward later that night, my mom called me crying about the incident (I was not actually present). I bought her some neosporin and went to visit her. I texted my grandma the following:

“Hello, can we please have confirmation that (sister’s) dog has had his rabies shots? My mom’s face is non stop bleeding all night and the skin is broken, wanting to make sure she’s not at risk for any potential diseases.” My grandma writes back accusing me of having a tone with her and I never did get an answer to my question. I was just trying to gather facts to ensure my mom was safe.

The next day I took off work to take my mom to the doctor. She had to get a tetanus shot and antibiotics. Thankfully the doctor says the paralysis on half her face should go away in about a month. My mom let my grandparents know that she asked the doctor to not report the incident. It seems like that’s all they care about- not that my mom was badly injured. My mom also expressed concerns about them being around the dog and their response was that they “trust the dog.” Which seems like a slap in the face to my mom considering how badly she is injured.

My mom gets a text 24 hours later from my sister (first time she bothered to reach out). The text just stated “Thank you for not reporting my dog. He is a protection dog and will be on high alert around anyone that he hasn’t seen interact positively with me. Thanks again.”

I am very upset that from my sister there was no apology, no checking if she is okay, no offering to pay her medical bill, no game plan to stop this from happening again etc. Just this awful excuse that seemed like it was half blaming my mom. This was not about protection, my mom was innocently watching TV and my sister wasn’t even present when it happened.

My grandparents also banned my 5lb gentle chiweenie from ever coming in their house again because my dog ran into the street when he was letting him go potty, yet he allows this aggressive dog to stay in his home no questions asked. It feels like a double standard.

Am I wrong for feeling upset with my family?